Machine for grinding cutters.



No. 760A-,926.

PATENTE!) MAY 24, 1904.

E. SGHROEDER. MACHINE FOR GRINDING CUTTBRS.

APPLIOATIONZFILED 00T. 27, 1 903.

2 SHEETS-SHEET 2 N0 MODEL.

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THE Norms warms co. Pnoraumo.. wAsmN Patented May 24, 1904.

PATENT OFFICE.

EMIL SCHROEDER, OF NEW YORK, N. Y.

MACHINE FORGRINDING CUTTERS.

SPECIFICATION forming part of Letters vPatent N o 760,926, dated May 24.-, 1904.

Application filed October 27, 1903.

To all whom it may concern: i

Be it known that I, EMIL SCHROEDER, a citizen of the United States, and a resident of the city of New York, (East New York, borough of Brooklyn,) in the county of Kings and State of New York, have invented a new and Improved Machine for Grinding Cutters, of which the following is a full, clear, and exact description.

The object of the invention is to provide a new and improved` machine ,more especially designed for accurately grinding rotary cutters-such, for instance, as is used in a fleshing and shaving machine for raw and dressed furs or skins, for which Letters Patent of the United States No. 741,553 has been granted to me on October 13, 1903.

The invention consists of novel features and parts and combinations of the same, as will be more fully described hereinafter and then pointed out in the claims.

A practical embodiment of the invention is represented in the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate correspondingparts in all the views.

Figure lis a front elevation of the improvement, parts being in section. Fig. 2 is a side elevation of the same. Fig. 3 is an' enlarged sectional plan view of the same. Fig. 4; is an enlarged sectional side elevation of the tool for forming the curry-knife edge on the cutter.v Fig. 5 is a cross-section of the cutter' after grinding, and Fig. 6 is a similar View o the finished cutter havingthe curry-knif e ge. y

The cutter A is in the form of a disk secured to a iiange A', extending integrally from a pulley A3, having its hub fastened on-a spindle A3, hung on centers B B, having handles B and screwing in bearing-blocks C', attached to the main frame C of the machine. The cutting edge f the cutter A is adapted to be engaged on opposite sides by the peripheral faces of grinding-wheels D D', made of emery or other suitable material and rotating toward each other, as plainly indicated by the arrows in Fig. l. The grinding-wheels D D are set one in front of the other, preferably, however, in such a manner that the rear face of Serial No. 178,694. (No model.)

the front grinding-Wheel D extends in the same plane as the front face of the rear grinding-wheel D. (See Fig. 3.) rlhe grinding- Wheels D D are fastened on shafts D2 D3, journaled in suitable bearings carried by slides E E', mounted to slide transversely on guideways E3, fastened in a slide F, mounted to slide vertically in guideways C2, carried on standards C3, forming, part of the main frame C.

vThe slides E E are adjusted transversely by `screw-rods E3 E", screwing the slides E and E and mounted to turn in cross-bars E E, attached to the outer ends of the guideways E2. The screw-rods E3 and E* are provided at their outer ends with handles E7 E3 under the 'control of the operator for turning the screwrods E3E4 to move the slides E and E trans- Versely on their guideways E2, thus shifting the grinding-wheels D and Dl correspondingly so as to bring the peripheral edges thereof in proper accurate position relative to the opposite faces of the cutter edge A4L of the cutter A. The slide F is adjusted vertically by a screw-rod F', screwing in the slide F and mounted to turn in suitable bearings on the standard C3, and on the upper end of the screwrod F is secured a handle F2, adapted to be .taken hold of by the operator to turn the On'thefshafts D2 and D3 of the grinding- Wh'eels D5 and D are secured pulleys G and G', around which passes a belt G2, also passing over an idler G3, journaled on a bracket G4, attached to the slide vF, so as to move up and down with the latter to insure the saine relation at all times between the idler G3 andthe.'

pulleys G and G. The belt G2 passes over a suitable overhead pulley on a counter-shaft, so as to impart a simultaneous rotary motion to the grinding-wheels D-and Dl In the direc- I oo tion above mentioned, and indicated by the arrows in Fig. l. v p l Over the pulley A2 of the cutter A passes a belt H, extending downwardly and passing around a pulley H', secured on a shaft I, journaled in suitable bearings in the lower part of the main frame C. On the shaft'I are fastened pulleys I and I2, of which the smaller pulley I is shown connected by a belt I3 with a pulley I4 on the main shaft J, likewise journaled on the main frame C and provided with fast and loose pulleys J', connected by a belt with other suitable machinery for imparting a rotary motion to the main shaft J. On the shaft J is also secured a pulley I2, adapted to be engaged by the belt I3 at the time it is desired to rotate the shaft I slower, the belt I3 then passing over the larger pulley I2. By the arrangement described two different speeds can be given to the-cutter A-that is, a high speed is given to the cutter A when grinding the cutting edge A4 thereof without taking the temper out of the steel-and when the cutter A is ground and its edge A4 is to be turned over to form a curry-knife edge A5 (see Fig. 6) then the slow speed is employed-that is, the belt I3 engages the pulleys I5 and I2.

The tool for turning the edge A4 over to form the curry-knife edge A5 forms the subject-matter of the divisional application Serial No. 184,558, filed by me December lO, 1903, and this tool is arranged as follows: A frictionroller K is journaled in the forked end K of a rod K2, mounted to slide in acarrier L, and a'portion of the rodfK2 is threaded and engaged by a nut K3, held against longitudinal movement in the carrier L. Now when the nut K3 is turned by the operator the rod K2 is caused to slide lengthwise in the carrier L, so as to bring the friction-roller K in proper relation to the edge A4 of the cutter A. The carrier L is fulcrumed at its forward end at Ll on a base-plate N, fastened by a bolt N to a swingplate O, hung on centers P, carried on the main frame C, to allow of swinging the said swingplate O over into a forward position when the tool is in use (sce Fig. 2)-that is, during the grinding operation of the cutter-or to allow of swinging the swing-plate O and the parts carried thereby into an inactive position, as shown in Figs. 3 and 4. rIhe bolt N', previously mentioned, extends through a longitudinal slot O', formed in the swing-plate, to allow of adjusting the base-plate lengthwise on the swing-plate, according to the size of the cutter A under treatment. By the arrangement described it will be seen that the operator in taking hold of the rod K2 can impart a swinging motion from the right to the left to the carrier L at the time the friction-roller K engages, say, the right-hand side of the edge A4, the friction-roller K at the time standing at an angle to the said edge A4. During the swinging motion given to the rod K2 by the operator the friction-roller K is caused to move bodily around and in doing so exerts a gradual pressure on the edge A4, so as to turn the same over to form the annular curry-knife edge A5. During this operation it is desirable to grease the edge A4, as well as the roller K, to insure a gradual and uniform laying over of thecutting edge without danger of injuring the same.

From the foregoing it will be seen that in order to bring the cutter A into a proper condition for lleshing and shaving purposes it is necessary to first grind an accurate circular and sharp cutting edge A4 and then turn the said edge over by the tool described, so as to produce the annular curry-knife edge A5. When this has been done, the operator turns the crank-handle F2 to move the grindingwheels D and D' upward and then swings the swing-plate O into a backward position, after which the handles B are turned so as to run the centers B out of engagement with the hub Asto allow of conveniently removing the cutter A from the grinding and laying-over m chine to permit of transferring the cutter to the fieshing and shaving machine.'

In practice the grinding-wheels are run at the rate of three thousand revolutions a minute to one hundred and fifty revolutions of the cutter during the grinding operation, and for laying or turning the edge A4 over the cutter is run about sixteen revolutions per minute. The grinding takes about ten minutes, and the overlaying operation or formation of the annular curry-knife edge'usually takes about live minutes; but for either operation it is not necessary to employ highlyskilled labor, as the proper adjustment can readily be made.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 1. In a grinding-machine for grinding circular cutters, the combination with a pair of driven grinding-wheels, arranged one in front of the other, and means for adjusting the grinding-wheels toward and from each other and up and down, of adjustable bearings, and a spindle journaled on the said bearings and carrying a pulley and a flange on which the circular cutter is secured, the said spindle, pulley-flange and cutter forming a unitary structure, removably and adjustably held in the said bearings, to bring the cutter and grinding-wheels in proper relation to each other and to allow of rotating the' cutter, as set forth.

2. A grinding-machine for grinding circular cutters, comprising a head mounted to slide up and down and provided with transverse guideways, means for adjusting the said head, slides mounted to move in the said guideways, means for moving the slides independently toward and from. each other, and grinding-wheels journaled in the said slides, one in front of the other, as set forth.

3. A grinding-machine for grinding circu- IOO lar cutters, comprising a head mounted to slide up and down and provided with transverse guideways, means for adjusting the said head, slides mounted to move in the said guide- 5- ways, means for moving the slides independently toward and from each other, grindingwheels jourualed in the said slides, one in front of the other, fixed bearing-blocks below the said grinding-wheels, centers screwing in IO the said bearing-blocks, and a spindle hung on the said centers and provided with a pulley and flange for carrying the disk to be ground, as set forth.

In testimony whereof I have signed my name to this specification in the presence of two sub- I 5 scribing witnesses.

' EMIL SCHROEDER. Witnesses:

THEO. G. HosTER, EVERARD B. MARSHALL. 

